In vehicles with automatic transmissions, the transmission is typically affixed to the engine in the following steps: The middle portion of a drive plate is fastened with screws to one end of a crankshaft via an adaptor; then the rim of the drive plate is coupled to the front cover of a torque converter with screws.
When the drive plate is screwed to the front cover, bolt coupling holes of each member should be exactly aligned. The bolt coupling holes are, however, obscured from view by a crank position sensor-wheel plate that is coupled to the rim of the drive plate. Therefore, the user must rotate the crankshaft or torque converter to align the bolt coupling holes of the drive plate and the front cover.